1947 Cluster Gear Endplay Opinion

[STEVE O]

Hi,
Have another question to get opinions on. In my quest to help my friend swap a 40 closed drive shaft transmission to open for his 47 pu my question involves cluster Gear endplay. His best case with good thrust washers measures .019 endplay . I see Mac at Vanpelts has a .023 shim washer. Should I find a way to grind the case and aim for .005 endplay or just use case as is? Thanks for all your help.
Steve